/* ----------------------------------------------------------------------
 * Project:      CMSIS DSP Library
 * Title:        arm_float_to_q7.c
 * Description:  Converts the elements of the floating-point vector to Q7 vector
 *
 * $Date:        18. March 2019
 * $Revision:    V1.6.0
 *
 * Target Processor: Cortex-M cores
 * -------------------------------------------------------------------- */
/*
 * Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved.
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed under the Apache License, Version 2.0 (the License); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "arm_math.h"

/**
  @ingroup groupSupport
 */

/**
  @addtogroup float_to_x
  @{
 */

/**
 * @brief Converts the elements of the floating-point vector to Q7 vector.
 * @param[in]       *pSrc points to the floating-point input vector
 * @param[out]      *pDst points to the Q7 output vector
 * @param[in]       blockSize length of the input vector
 * @return none.
 *
 *\par Description:
 * \par
 * The equation used for the conversion process is:
 * <pre>
 * 	pDst[n] = (q7_t)(pSrc[n] * 128);   0 <= n < blockSize.
 * </pre>
 * \par Scaling and Overflow Behavior:
 * \par
 * The function uses saturating arithmetic.
 * Results outside of the allowable Q7 range [0x80 0x7F] will be saturated.
 * \note
 * In order to apply rounding, the library should be rebuilt with the ROUNDING macro
 * defined in the preprocessor section of project options.
 */
#if defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE)
void arm_float_to_q7(
	const float32_t *pSrc,
	q7_t *pDst,
	uint32_t blockSize)
{
	uint32_t         blkCnt;     /* loop counters */
	float32_t       maxQ = powf(2.0, 7);
	f32x4x4_t       tmp;
	q15x8_t         evVec, oddVec;
	q7x16_t         vecDst;
	float32_t const *pSrcVec;
#ifdef ARM_MATH_ROUNDING
	float32_t in;
#endif

	pSrcVec = (float32_t const *) pSrc;
	blkCnt = blockSize >> 4;
	while (blkCnt > 0U) {
		tmp = vld4q(pSrcVec);
		pSrcVec += 16;
		/*
		 * C = A * 128.0
		 * convert from float to q7 and then store the results in the destination buffer
		 */
		tmp.val[0] = vmulq(tmp.val[0], maxQ);
		tmp.val[1] = vmulq(tmp.val[1], maxQ);
		tmp.val[2] = vmulq(tmp.val[2], maxQ);
		tmp.val[3] = vmulq(tmp.val[3], maxQ);

		/*
		 * convert and pack evens
		 */
		evVec = vqmovnbq(evVec, vcvtaq_s32_f32(tmp.val[0]));
		evVec = vqmovntq(evVec, vcvtaq_s32_f32(tmp.val[2]));
		/*
		 * convert and pack odds
		 */
		oddVec = vqmovnbq(oddVec, vcvtaq_s32_f32(tmp.val[1]));
		oddVec = vqmovntq(oddVec, vcvtaq_s32_f32(tmp.val[3]));
		/*
		 * merge
		 */
		vecDst = vqmovnbq(vecDst, evVec);
		vecDst = vqmovntq(vecDst, oddVec);

		vst1q(pDst, vecDst);
		pDst += 16;
		/*
		 * Decrement the blockSize loop counter
		 */
		blkCnt--;
	}

	blkCnt = blockSize & 0xF;
	while (blkCnt > 0U) {
		/* C = A * 128 */

		/* Convert from float to q7 and store result in destination buffer */
#ifdef ARM_MATH_ROUNDING

		in = (*pSrcVec++ * 128);
		in += in > 0.0f ? 0.5f : -0.5f;
		*pDst++ = (q7_t)(__SSAT((q15_t)(in), 8));

#else

		*pDst++ = (q7_t) __SSAT((q31_t)(*pSrcVec++ * 128.0f), 8);

#endif /* #ifdef ARM_MATH_ROUNDING */

		/* Decrement loop counter */
		blkCnt--;
	}

}
#else
#if defined(ARM_MATH_NEON)
void arm_float_to_q7(
	const float32_t *pSrc,
	q7_t *pDst,
	uint32_t blockSize)
{
	const float32_t *pIn = pSrc;                         /* Src pointer */
	uint32_t blkCnt;                               /* loop counter */

	float32x4_t inV;
#ifdef ARM_MATH_ROUNDING
	float32_t in;
	float32x4_t zeroV = vdupq_n_f32(0.0f);
	float32x4_t pHalf = vdupq_n_f32(0.5f / 128.0f);
	float32x4_t mHalf = vdupq_n_f32(-0.5f / 128.0f);
	float32x4_t r;
	uint32x4_t cmp;
#endif

	int16x4_t cvt1, cvt2;
	int8x8_t outV;

	blkCnt = blockSize >> 3U;

	/* Compute 8 outputs at a time.
	 ** a second loop below computes the remaining 1 to 7 samples. */
	while (blkCnt > 0U) {

#ifdef ARM_MATH_ROUNDING
		/* C = A * 128 */
		/* Convert from float to q7 and then store the results in the destination buffer */
		inV = vld1q_f32(pIn);
		cmp = vcgtq_f32(inV, zeroV);
		r = vbslq_f32(cmp, pHalf, mHalf);
		inV = vaddq_f32(inV, r);
		cvt1 = vqmovn_s32(vcvtq_n_s32_f32(inV, 7));
		pIn += 4;

		inV = vld1q_f32(pIn);
		cmp = vcgtq_f32(inV, zeroV);
		r = vbslq_f32(cmp, pHalf, mHalf);
		inV = vaddq_f32(inV, r);
		cvt2 = vqmovn_s32(vcvtq_n_s32_f32(inV, 7));
		pIn += 4;

		outV = vqmovn_s16(vcombine_s16(cvt1, cvt2));
		vst1_s8(pDst, outV);
		pDst += 8;

#else

		/* C = A * 128 */
		/* Convert from float to q7 and then store the results in the destination buffer */
		inV = vld1q_f32(pIn);
		cvt1 = vqmovn_s32(vcvtq_n_s32_f32(inV, 7));
		pIn += 4;

		inV = vld1q_f32(pIn);
		cvt2 = vqmovn_s32(vcvtq_n_s32_f32(inV, 7));
		pIn += 4;

		outV = vqmovn_s16(vcombine_s16(cvt1, cvt2));

		vst1_s8(pDst, outV);
		pDst += 8;
#endif /*      #ifdef ARM_MATH_ROUNDING        */

		/* Decrement the loop counter */
		blkCnt--;
	}

	/* If the blockSize is not a multiple of 4, compute any remaining output samples here.
	 ** No loop unrolling is used. */
	blkCnt = blockSize & 7;

	while (blkCnt > 0U) {

#ifdef ARM_MATH_ROUNDING
		/* C = A * 128 */
		/* Convert from float to q7 and then store the results in the destination buffer */
		in = *pIn++;
		in = (in * 128);
		in += in > 0.0f ? 0.5f : -0.5f;
		*pDst++ = (q7_t)(__SSAT((q15_t)(in), 8));

#else

		/* C = A * 128 */
		/* Convert from float to q7 and then store the results in the destination buffer */
		*pDst++ = __SSAT((q31_t)(*pIn++ * 128.0f), 8);

#endif /*      #ifdef ARM_MATH_ROUNDING        */

		/* Decrement the loop counter */
		blkCnt--;
	}

}
#else
void arm_float_to_q7(
	const float32_t *pSrc,
	q7_t *pDst,
	uint32_t blockSize)
{
	uint32_t blkCnt;                               /* Loop counter */
	const float32_t *pIn = pSrc;                         /* Source pointer */

#ifdef ARM_MATH_ROUNDING
	float32_t in;
#endif /* #ifdef ARM_MATH_ROUNDING */

#if defined (ARM_MATH_LOOPUNROLL)

	/* Loop unrolling: Compute 4 outputs at a time */
	blkCnt = blockSize >> 2U;

	while (blkCnt > 0U) {
		/* C = A * 128 */

		/* Convert from float to q7 and store result in destination buffer */
#ifdef ARM_MATH_ROUNDING

		in = (*pIn++ * 128);
		in += in > 0.0f ? 0.5f : -0.5f;
		*pDst++ = (q7_t)(__SSAT((q15_t)(in), 8));

		in = (*pIn++ * 128);
		in += in > 0.0f ? 0.5f : -0.5f;
		*pDst++ = (q7_t)(__SSAT((q15_t)(in), 8));

		in = (*pIn++ * 128);
		in += in > 0.0f ? 0.5f : -0.5f;
		*pDst++ = (q7_t)(__SSAT((q15_t)(in), 8));

		in = (*pIn++ * 128);
		in += in > 0.0f ? 0.5f : -0.5f;
		*pDst++ = (q7_t)(__SSAT((q15_t)(in), 8));

#else

		*pDst++ = __SSAT((q31_t)(*pIn++ * 128.0f), 8);
		*pDst++ = __SSAT((q31_t)(*pIn++ * 128.0f), 8);
		*pDst++ = __SSAT((q31_t)(*pIn++ * 128.0f), 8);
		*pDst++ = __SSAT((q31_t)(*pIn++ * 128.0f), 8);

#endif /* #ifdef ARM_MATH_ROUNDING */

		/* Decrement loop counter */
		blkCnt--;
	}

	/* Loop unrolling: Compute remaining outputs */
	blkCnt = blockSize % 0x4U;

#else

	/* Initialize blkCnt with number of samples */
	blkCnt = blockSize;

#endif /* #if defined (ARM_MATH_LOOPUNROLL) */

	while (blkCnt > 0U) {
		/* C = A * 128 */

		/* Convert from float to q7 and store result in destination buffer */
#ifdef ARM_MATH_ROUNDING

		in = (*pIn++ * 128);
		in += in > 0.0f ? 0.5f : -0.5f;
		*pDst++ = (q7_t)(__SSAT((q15_t)(in), 8));

#else

		*pDst++ = (q7_t) __SSAT((q31_t)(*pIn++ * 128.0f), 8);

#endif /* #ifdef ARM_MATH_ROUNDING */

		/* Decrement loop counter */
		blkCnt--;
	}

}
#endif /* #if defined(ARM_MATH_NEON) */
#endif /* defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE) */

/**
  @} end of float_to_x group
 */
